both substrate and cofactor since neither (+)-epoxydon, an epimer of (+)-isoepoxydon, nor NADH was utilized. Cell extracts of the parent and of mutant J2, which is blocked before the epoxides in the patulin pathway, were found to convert phyllostine and isoepoxydon to a number of unknown metabolites which appeared as yellow spots on thin-layer chromatograms after spraying with a chromogenic reagent. Extracts
发现青霉菌(NRRL 2159A)及其Pat突变体J2,J1和S11的无细胞
提取物含有明显的
NADP依赖的异环氧脱氢酶活性。环氧(-)-叶绿素和(+)-异环氧的这种可逆互变最佳在pH 5.8发生,并完全被1 mM
对氯汞苯甲酸(PCMB)抑制。由于未使用(+)-环氧树酯,(+)-异环氧树酯的差向异构体或
NADH,因此胞质溶胶酶对底物和辅因子均具有特异性。发现母体和突变体J2的细胞
提取物在巡视蛋白途径中的
环氧化物之前被封闭,可以将phyllostine和isoepoxydon转化为许多未知代谢物,这些代谢物在用发色剂喷雾后在薄层色谱图中显示为黄色斑点。突变体J1的
提取物无法进行这种转化,而突变体S11的整个细胞却积累了这些相同的“黄色”化合物。由于PCMB处理过的J2
提取物将phyllostine而不是isoepoxydon转化为这些新的代谢产物,因此phyllostine似乎是它们更直接的前